Refrigeration



Juy 14,1942. T. K s-HERWOOD 2,289,809

l REFRIGERATION Filed July 50, 1940 is colder than that inthe lower regions.

PatentedJuly 1 942 azsasoa REFRIGERATION Thomas K. Sherwood, Wellesley, lMass.,uassignor` to Servei, Inc., New of Delaware York. N. Y., a corporation Application July so, 1940, serial No. 348,466

, 1o claims. (o1. ca -1)'l At night, the atmosphere inthe upper regions Therefore, on clear nights a good radiating surface will radiatestrongly toward the Vsky and receive very little radiation in return. What is received comes for the most part from the air, which like all gases is a very poor radiator. Cloudy nights' are limpossible for effective radiation towards the sky, since clouds radiate toward the earth and also form a barrier against radiation toward the upper cold regions of the atmosphere.

One object of the presentv invention is to employ a new and improved economical method and apparatus for utilizing natural atmospheric conditions and phenomena for cooling purposes.

Another object is Ito provide new and improved economical metho'dand apparatus, which utilize natural atmospheric conditions and phenomena for cooling water, and which dispense with the usual power and heating expedients commonly employed in refrigerating systems.

Another object is to provide method and apparatus, which utilize` the radiating 'phenomena above referred to in conjunction 4with convection principles, to cool water' either on a cool night by 2 convection or .on al clear night by radiation.

My improved method and apparatus may be employed for instance in the water-cooling systems oi' power plants inplace of the usual cooling `devices such as spray fountains or cooling towers, or may be employed to supplement the use of these devices. It may also be employed to cool nary convection bank with nned tubing is exposed to the outside air.

The condenser coils I3 and I5 are connected in parallel to an evaporator coil I8. The evaporator coil I6 is located below the two condenser coils I3 and I5 to permit vgravity flow of liquid from the condensers to the evaporator. The evaporator coil I6 is. immersed in material tobe' cooled, such as water, held in fan insulated'receptacle or tank I9. The|upper end of evaporatorcoil I6 is connected to the lower end-of a conduit I1. The upper end of conduit I1 is branched and connected to the vaporinlet ends of-both condensers I3 and I5. The lower end oi evaporator coil I6 is connected to the lowerend of a conduit I8. The upper end of conduit I8 is branched and is connected to the liquid outlet ends of both condensers I3 and I5. The condenser coils I3 and Ii and the evaporator coil I6.

perature. This will cause the temperature of the condenser I I in heat exchange relationship therewith to drop below that of the water in the tank le, so that the liquid refrigerant in .the 4 water to be used directly for air-cooling purposes or for a condenser in a refrigerating system.

Various other objects .of the invention will be apparent from the following particular description and from an inspection of the accompanying drawing, showing somewhat diagrammatically and partly in section an apparatus, which embodies the structural features of the invention,

and which can be used to carry out the method of said invention.

For carrying out my new and improved method. l

a radiating member, desirably in the form of a fiat metal plate Ill is horizontally mounted outdoors toexpose 'its upper radiatingsurface II of substantial area to the sky. This surface II deslrably has a dull black or similar coating of high radiating capacity, and is protected against air circulation by baiiies l2 extending around the sides thereof.

A condenser coil IlA is disposed in good thermal contact with the bottom face of the plate I0, and

v is well insulated below by suitable insulation I 4.

evaporator coil I6 will boil and said water will cool.

If the air is cool but the sky is overcast, theV convection coil I5 will take the load, since the clouds will interfere with etl'ective radiation from the. plate I0. Under these atmospheric conditions, the temperature of the convection coil I 5 will drop below that of the water in the tank I9.- and the resultant boiling of the'liquid refrigerant will cool the water in the tank I8.

The water tank I9 is large enough to supply refrigeration duringl the day by virtue ci the cooling accomplished during the night.

It the atmospheric conditions are such as to maintain the temperature or the condensers I3 and I5 above the water'temperature, the system ceases to `function.l y

It should be notedthat the whole system acts `as a heat valve because the liquid condensed flows by gravity only in one direction indicated tothe evaporator coil IB. V j

Although certain novel features of the invention have been shown and described and are pointed out in the annexed claims, it will beunderstood that various omissions. substitutions A second condenser coil Il in the form of an ordiand changes in the several steps oi the method and in its operation and in the form and details of the apparatus illustrated may be made by those skilled in the art without departing from the spirit of the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

l. Cooling apparatus comprising a radiation surface exposed for radiation towards the sky and shielded against flow of ambient air in contact therewith, and conduits for conducting heat transfer fluid in a path of, flow having a heat dissipating part in heat exchange relation with said surface, and a heat absorbing part in heat ex- Y change relation with a medium to be cooled.

2. Cooling apparatus comprising conduits for conducting heat transfer fluid in a path of flow having a part in heat exchange relation with a medium to bel cooled, a radiation surface arlranged in heat exchange'relation with another part of said path of fluid flow, said radiation surheat rejecting parts having a radiation surface exposed for radiation towards the sky and shielded against convection of air in contact therewith.

7. Cooling apparatus comprising a circuit for volatile heat transfer fluid having a plurality of condensers connected in parallel to an evaporator at a level below that of said condensers so that fluid condensed to liquid in the condensers iiows by gravity to the evaporator, one of said the sky is clear, said surface is cooled by radiaconductive plate having a 'radiating surface exposed to the sky for radiation towards the sky, a condenser in thermal exchange relation with the other sur-'face of said plate, a container for water `'to be cooled, and an evaporator in cooling relation with water in said container, and connected to said condenser wall to form therewith a circuit for volatile heat transfer iiuid.

4. pooling apparatus comprising a circuit for heat transfer fluid having a plurality of heat rejecting parts and a heat receiving part, one of said heat rejecting part" being constructed and arranged for heat transfer to a cooling fluid owing in heat exchange relation therewith, and 'another of said heat rejecting parts having a radiation surface exposed for radiation towards the sky.

5. Cooling apparatus comprising a circuit-for heat transfer fluid having a plurality of hea't re- Jecting parts'connected in parallel to a heat receiving part, one 'of said heat rejecting parts be-J ing constructed and arranged for heat transfer to a cooling fluid flowing in heat exchange relation therewith, and another of said heat rejecting parts having a radiation surface exposed for radiation towards'v the sky.

6. Cooling apparatus comprising a circuit for volatile heat transferV fluid having a plurality of heat rejecting parts connected in parallel to a heat receiving part, one of said heat rejecting parts being constructed and arranged for heat transfer to convection air, and another of said tion below the ambient temperature to cause condensation of the vaporous heat transfer *fluid at a temperature and pressure lower than that obtainable by cooling with ambient air, and carrying out said vaporizing of heat transfer iluid at said lower pressure and temperature so as to cool the medium toa temperature below ambient temperature.

9. A method of cooling which comprises transferring heat'from a' medium to be cooled to vaporize a volatile heat transfer uid, flowing the resulting vapor into heat exchange relation with ambient air andalso in -heat exchange relation with a radiation surface exposed for radiation towards the sky and shielded from ambient air, so that said vapor is condensed to liquid by heat transfer to ambient air or said surface, whichever is at the lower temperature, and again vaporizing the liquid by heat transfer lfrom the medium to be cooled. y

10. A method of cooling which comprises transferring heat from a medium to be cooled to a volatile heat transfer fluid to cause vaporizatior of said iiuid, flowing the resulting vapor upward and into heat transfer relation with a heat receiving uid and also a radiation surface ex posed for radiation towards the sky but otherwise shielded against heat transfer, so that the vaporous heat transfer fluidis condensed to liquid by heat transfer either to said heat receiving fluid or to said surface, whichever is at the lower temperature, and returning the condensate by gravity (flow into heat exchange relation with said medium to be cooled. i

THOMAS K. sHEawooD. 

